The compound interest (in ₹) on ₹ $5,000$ for $3$ years at $10 \%$ per annum will amount to:

$A$ sum of money placed at compound interest doubles itself in $4$ $years$. In how many $years$ will it amount to four times itself?

Mr. Dua invested money in two schemes $A$ and $B$ offering compound interest at $8 \%$ per annum and $9 \%$ per annum respectively. If the total amount of interest accrued through two schemes together in two years was ₹ $4818.30$ and the total amount invested was ₹ $27000$. What was the amount (in ₹) invested in scheme $A$?

If the rate of interest is $4 \%$ per annum for the first year,$5 \%$ per annum for the second year,and $6 \%$ per annum for the third year,then the compound interest on $Rs. 10000$ for $3$ years will be (in $Rs.$):

On what sum will the compound interest (in ₹) for $2 \frac{1}{2}$ years at $10 \%$ per annum amount to ₹ $6352.50$?

Find the compound interest on $Rs. 32000$ at $20 \%$ per annum for $1$ year,compounded half-yearly (in $Rs.$).